Waterproofing of textile materials



atented Mar. 25, 1941 PATENT OFFICE WATERPROOFING F TEXTILE MATERIALS Fernand Frederic Schwartz, Paris, France, as-

slgnor, by direct and meme assignments, to American Ecla Corporation, Dover, Del., a corporation of Delaware No Drawing. Application December 10, 1936, Serial No. 115,267. In France December 19,

4 Claims. (CL 9168) ing to the waterproofing of textile materials. It is known that aluminium acetate or other aiuminates can be employed for the waterproofa ing oi textile materials. The use of these substances, however, has hitherto involved preliminary treatment of the fabric and, in order to obtain the best results, the treatment of the fabric alter impregnation, these latter treatments con- W sisting of soap'ing. and the application of a wax emulsion or a similar treatment.

it is also known to apply to fabrics including teirtile iabrics a liquid coating which forms a Water impermeable film on the surface of the w i'abric.

r it is an object of the present invention to modiiy the method of waterproofing fabrics with aluminium salts, e. g., aluminium acetate,

so as to simplify the process of impregnation it and to render it cheaper and more efl'ective.

The present invention deals exclusively with a process of this nature and excludes any process in which a like or coating of water impermeable material is formed over the surface of a textile iii fabric.

' it has now been found that impregnation of textile materials with-aluminium salts, e. g., with aluminium acetate may be facilitatedby the addition to an aqueous solution of the aluminium so salt of a proportion of a substance which lowers.

the surface tension of. the solution and thus enables it to penetrate the textile material readily. The present invention accordingly comprises a process for the waterproofing of textile mate- 35 rials with a solution of a salt of aluminium which comprises the addition to the aqueous solution of" 'a proportion of an organic vsubstance which lowers the surface tension of the solution. The

organic liquid may have a boiling point below 40 130 C. and may thus be-removed substantially completely together with the water by heating the impregnated textilematerial. v

The added organic substance is preferably a liquid which is not miscible with water in all 45 proportions, At the same time the organic liquid selected should be one which is compatible with the aqueous solution of aluminium salt,-

i. e. one which does not throw the aluminium salt out of solution and is not itself thrown out 50 of solution bythe aluminium'salt.

The organic liquid may conveniently consist of an alcohoior ketone having a boiling point not exceeding 130 0. Among the'alcohols it has been found that butyl andisobutyl alcohols 55 may be employed with advantage.

I I invention is for improvements in or relat- The waterproofing agent may be an aluminium salt of an organic acid such as aluminium acetate or aluminium lactate.

When dipped into an aqueous solution of aluminium salt containing the added organic sub- 5 stance the textile material is wetted through and through immediately and upon removal from the solution and drying it may be freed from water and from the organic substance, the salt remaining precipitated on the fibres of the tex- 1 tile material in finely subdivided and insoluble orm.

The present invention also provides a waterproofing liquid consisting of a dilute aqueous organic solution of an organic aluminium salt.

Following is a description by way of example of two methods of carrying the invention into efl'ec Example I Example If A fabric is waterproofed by dipping it into a 3% aqueous solution of aluminium lactate containing about 8% of isobutyl alcohol. The

dipped fabric is dried in order to remove water and organic liquid. Again, the fabric is rendered completely waterproof.

I claim:

1. The herein described process for rendering a textile material water-repellent by means of an aluminum salt which remains precipitated on the fibres of the material in finely subdivided and insoluble form, which comprises treating the textile material with a liquid consisting of an organic acid selected from the group con- 'sisting of acetic acid and lactic acid mixed with a solution which with the acid will form an aluminum salt and a proportion of an organic liquid wetting agent, which wetting. agent (a) is an alcohol selectedi'rom the group consisting of butyl alcohol and isobutyl alcohol, (b) is compatible with the said aqueous solution of the aluminum salt in the concentration employed, (c)

lowers the surface tension of the solution, (d) u has a boiling point not exceeding 130 C., and drying the treated textile materialto remove the organic liquid wetting agent.

2. The herein described process for renderin a textile material water-repellent by means of an aluminum salt which remains precipitated on the fibres oi the material in finely subdivided and insoluble form, which comprises treating the textile material with a liquid consisting substantially of a 3% aqueous solution of a salt selected from the group consisting of aluminum acetate and aluminum lactate mixed with substantially 8% of an alcohol selected from the group consisting of butyl alcohol and isobutyl alcohol, and thereafter drying the treated textile material to expel the alcohol therefrom.

3, The herein described process 101' rendering a textile material water-repellant by means of an aluminum salt which res precipitated on the fibres of the material in finely suvided and insoluble form, which comprises treating the textile material with a liquid consisting substantially of a 3% aqueous solution of a salt selected from the group consisting of aluminum acetate and aluminum lactate mixed with substantially 8% of butyl alcohol, and thereafter drying the treated textile material to expel the alcohol therefrom.

a. A process for rendering a. textile material water-repellant by means of an aluminum salt which remains precipitated on the fibres of the material in finely subdivided and insoluble form, which process comprises dipping the textile material into a liquid consisting of substantially a 3% aqueous solution of aluminum acetate to which has been added about 8% ot-butyl alcohol, and thereafter drying the treated textile material to remove the butyl alcohol therefrom.

AND FREDERIC SCHWARTZ. 

